NASA has nailed an engine test on a spacecraft 13 billion miles away. It took more than 19 hours to even know if they were successful.

Last week, ground controllers sent commands to fire backup thrusters on Voyager 1, our most distant spacecraft. The thrusters had been idle for 37 years, since Voyager 1 flew past Saturn. To NASA's delight, the four dormant thrusters came alive.